作业帮计算：1.(-6y+x)(-6y-x) 2.(-6y+x)(6y-x) 3.(x+4y)(x-9y) 4.(-6y-x)(6y-x)
来源：学生作业帮助网 编辑：作业帮 时间：2024/11/24 03:28:56
计算：1.(-6y+x)(-6y-x) 2.(-6y+x)(6y-x) 3.(x+4y)(x-9y) 4.(-6y-x)(6y-x)
计算：1.(-6y+x)(-6y-x) 2.(-6y+x)(6y-x) 3.(x+4y)(x-9y) 4.(-6y-x)(6y-x)
计算：1.(-6y+x)(-6y-x) 2.(-6y+x)(6y-x) 3.(x+4y)(x-9y) 4.(-6y-x)(6y-x)
1.(-6y+x)(-6y-x)
=[-(6y-x)][-(6y+x)]
=(6y-x)(6y+x)
=(6y)²-x²
=36y²-x²
2.(-6y+x)(6y-x)
=[-(6y-x)](6y-x)
=-(6y-x)(6y-x)
=-[(6y-x)²]
=-（36y²-12xy-x²）
=x²+12xy-36y²
3.(x+4y)(x-9y)
=（x+4y)(x-4y-5y）
=（x+4y）[(x-4y)-5y]
=（x+4y）²-5y(x+4y)
=(x²+8xy+16y²）-（5xy+20y²）
=x²+3xy-4y²
4.(-6y-x)(6y-x)
=[-(6y+x)](6y-x)
=-(6y+x)(6y-x)
=-(36²-x²)
=x²-36y²
啊是各提一个负号（6y-x)(6y+x) =36x2-x2 (-6y+x)(6y-x)=-36y2+6xy+6xy+ -x2
(x+4y)(x-9y)=x2-9xy+4xy-36y2=x2-5xy-36y2
(-6y-x)(6y-x)=(x+6y)(x-6y)=x2-36y2
1.(-6y+x)(-6y-x)
=(-6y)²-x²
=36y²-x²
2.(-6y+x)(6y-x)
=-(6y-x)(6y-x)
=-(6y-x)²
=-(36y²-12y+x²)
=-36y²+12y-x²
3.(x+4y)(x-9y...
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1.(-6y+x)(-6y-x)
=(-6y)²-x²
=36y²-x²
2.(-6y+x)(6y-x)
=-(6y-x)(6y-x)
=-(6y-x)²
=-(36y²-12y+x²)
=-36y²+12y-x²
3.(x+4y)(x-9y)
=x²-9xy+4xy-36y²
=x²-5xy-36y²
4. (-6y-x)(6y-x)
=(-x-6y)(-x+6y)
=(-x)²-(6y)²
=x²-36y²
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